speed optimization and security of websites

We have 2 wordpress sites and we need a team /developer to maintain security on our server /site and optimize page speed all the time. To maintain security, you have to monitor the sites by checking all the threats that might harm the webs, update plugins, theme , etc. If the site is down by any reason , you must be able to find the reason and prevent it in the future. You should make a copy of the sites both daily and keep them 3 days before deleting and weekly.

We will pay monthly and this is a long term relationship as long as we are satisfied.
Please quote the price monthly
the speed should be less than 3 sec and A on page speed test all the time. We have CDN with stackpath.